Any Arcades in Germany?

AFAIK no unless somebody imports it privately and I didn't know.

 

When the game starts, it says that this game can be played only in Japan (or something like that, I can not quote what was written there), so, logically assume, that officially there can be no acrade machines in other parts of planet excluding Japan.
But, of cource, given that fact that the game itself was stolen from arcade machines long time ago and official arcade controller can be bought somewhere in the Internet - there is no problem to totally re-create arcade at home relatively inexpensive (given how much arcade machine can cost complitely).

 

While it does say that what you say is incorrect. Round1 in Japan and Round1 USA in the US has the rights for public usage of the machines. I think for a hefty fee anyone can import a machine and use it. Round1 is the only place that has the direct licensing/affiliation with Sega for usage of the machine. Otherwise, yes... an individual can import the machine and then implement / apply the offline mode patch that allows the game to function offline away from Sega's prying internet eyes.

But if you're adventurous, you can source the AFT dump (I won't link you.. Google is your friend) and run it on your computer, since in essence it's a PC game running in a cabinet on essentialy Intel Core i3-based hardware with an nVidia GTX 660 Ti or something of that generation of GPUs. If you have any kind of PC with a relatively modern and capable nVidia GPU you can run the dump with little to no issues. I am NOT condoning the act of grey area piracy that this would require... Do it at your own risk and use common sense. It does seem safe to stream it to YT/Twitch etc, but still have your wits about you.

With that said, unless you have a Hori-style arcade layout USB controller for the PS3/PS4 that works on PC as well you won't be getting the most authentic experience. Sure you can play with a PS3/PS4 DualShock controller, but then you might as well be playing F/F2nd/X. There's that fact, and that most HDTVs and/or computer displays have input lag/delay, and it's very important to have as little of that as possible when playing a music rhythm game like Project Diva. Wearing headphones mitigates that problem, but it sucks when you wanna play with friends and then they can't hear the music and gameplay.